Breaking functions

Character boundary analysis identifies the boundaries of "Extended
Grapheme Clusters", which are groupings of codepoints that should be
treated as character-like units for many text operations. Please see
Unicode Standard Annex #29, Unicode Text Segmentation,
http://www.unicode.org/reports/tr29/ for additional information on
grapheme clusters and guidelines on their use.

Word boundary analysis is used by search and replace functions, as well
as within text editing applications that allow the user to select words
with a double click. Word selection provides correct interpretation of
punctuation marks within and following words. Characters that are not
part of a word, such as symbols or punctuation marks, have word breaks on
both sides.